Reductive cross-coupling of N -acyl pyrazole and nitroarene using tetrahydroxydiboron: synthesis of secondary amides.

We report on a new method for the synthesis of amides using acyl pyrazoles and nitroarenes under reducing conditions. It was found that acyl pyrazoles react with organo-nitro compounds in the presence of B 2 (OH) 4 , giving the corresponding amides in good yields. We demonstrated that benzoyl pyrazoles having various substituents and nitroarenes with different substituents can be used to produce a range of N -substituted benzamides. The method shows good functional group tolerance and has potential application in the synthesis of a variety of organic molecules.